Guide to Assembling a Complete BMX

When you purchase a complete BMX bike, most parts come pre-assembled. However, the handlebars, pedals, and front wheel are detached to fit the bike into a compact box.

Constructing a complete BMX bike is straightforward if you adhere to the video instructions and steps outlined below. Your brand new complete BMX will be ready in a jiffy!

Assembling the bike offers you a unique opportunity to understand it thoroughly. As a passionate BMX enthusiast, there's nothing quite like providing your new bike with some tender loving care before your inaugural ride.

If you're hesitant about assembling it personally or lack previous experience with bikes, it's strongly advised to take it to a specialist shop.

Essential Tools for Assembling a Complete BMX Bike

Only a handful of tools are required to begin.

Allen keys
Wrenches
Open-ended 15 mm wrench for pedals
Air pump

Explore our range of BMX Tools - We have everything you need!

Step-by-Step Guide - Unboxing and Assembly of a Complete BMX

Initially, remove all plastic and foam, and unpack every item, ensuring that nothing is missing from the package.

Initial assembly stage

Lubricate the pedal bolts.
Determine the left and right pedals.
Rotate the right pedal clockwise - use a wrench to secure it.
Rotate the left pedal anticlockwise - secure it fully with a wrench.
Loosen the stem bolts.
Detach the stem faceplate.
Apply grease to the stem bolts.
Position the handlebar.
Place the faceplate over the stem, ensuring the knurled section of the handlebar is centred in the stem.
Tighten the stem bolts in a cross pattern – at this phase, it’s not necessary to fully tighten the faceplate.
Loosen the top cap/compression bolt with an Allen key.
Align the handlebars with the fork.

Now, you're prepared to attach the front wheel:

Loosen the front axle nuts almost entirely to make room for the fork dropouts.
Tighten the nuts using your fingers.
Fully tighten the nuts with a wrench.
Slide the BMX seat into the seat tube, you might want to lubricate the inside of the clamping area making future seat post removal easier.)
Secure the seat clamp using an Allen key.

With the seat in place, you can adjust the handlebars and fork alignment while seated on the bike. This process simplifies perfect adjustments:

Align the bar with the fork – the front wheel serves as your guide.
Tighten the top cap/compression bolt using an Allen key.
Finalise the stem tightening utilising a cross pattern, meaning you always tighten the bolt diagonally opposite the one you’ve just tightened.
Ensure there's an even gap between the stem faceplate and the stem itself - it's vital that the faceplate is tightened evenly.

Before setting out on your BMX, verify a few final aspects:

Inspect the chain - if it moves more than 2 centimetres, it's too loose – this can be rectified by loosening the wheel and pulling it backwards until the chain is correctly tightened.
Ensure all nuts and bolts are securely tightened.
Inflate the tyres to the advised pressure (marked in PSI on the tyre's side).
Detach the valve cap and attach the pump.
Inflate the tyre and replace the valve cap.
Repeat on the alternate wheel.
Now you're prepared to ride!

Explore our entire range of complete BMX Bikes.

If you require more comprehensive instructions for brake installation, see: How to Mount a BMX Brake.